| Index: third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp | 
| diff --git a/third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp b/third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp | 
| index 5eef8486a3ba1f1926a0aaf780173a5a5a686a53..5add5329865fd6ba67eda705e647cb0efc4247c8 100644 | 
| --- a/third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp | 
| +++ b/third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp | 
| @@ -1013,10 +1013,11 @@ void ReplaceSelectionCommand::doApply() | 
| applyCommandToComposite(BreakBlockquoteCommand::create(document())); | 
| // This will leave a br between the split. | 
| Node* br = endingSelection().start().anchorNode(); | 
| -        ASSERT(isHTMLBRElement(br)); | 
| -        // Insert content between the two blockquotes, but remove the br (since it was just a placeholder). | 
| -        insertionPos = positionInParentBeforeNode(*br); | 
| -        removeNode(br); | 
| +        if (isHTMLBRElement(br)) { | 
| +            // Insert content between the two blockquotes, but remove the br (since it was just a placeholder). | 
| +            insertionPos = positionInParentBeforeNode(*br); | 
| +            removeNode(br); | 
| +        } | 
| } | 
|  | 
| // Inserting content could cause whitespace to collapse, e.g. inserting <div>foo</div> into hello^ world. | 
|  |